Unloader for compressors



May 26, 1925. 1,539,269

A.F.PARKS' UNLOADER FOR COMPRESSCRS Filed Aug. 15, 1924 2 Sheets-Sheet l h u v51 N N g N o N o N Qi h N N ZgL/ h w N INVENTOR. 9| leflEPaz'zs ATTORNEYS.

May 26, 1925. 1,539,269

A. F, PARKS UNLOADER FOR COMPRESSORS INVENroR. .lb art Palks g g Z .QMToRNEx/s.

Patented May 26, 1925. l i' j o ,Y

U ELST @E1-NT QE 'Fi Amare@ relnfefevSOU-fer mweeelew Assieme nommen To LIZ whom t may onoem.: anda higlnpressure ,cylinder ll, in .teach Be it known that Annen@ F.;.PAR1s,.a citi.v 1 of vwhich `a .recipreealt-OryL ipitonl is 'er-, 55 zen ot the United Stated-andresident otnaiiged and,.operatedthrough,e piston,rodI South Norwallndn `the.f countyy of Fairfield fronde suitable, souree of power, ,as a 5 and StateotConnecticut, hasinventedcerfny 1i1otorclriven ieeeentric. Thelow "pressure tain new. and useful llnproveinents'in Unw eyliudeiyis providedat each,,end witlninlet v leaders lor Compressors, f which the .tolnvalves, :indicated gene1ally;as,l4, in whielrc() lowing,- s a speeifleation-u 'thepresentgunloader,meansare ilwerpotateh Y The present invention vrelates -to. an.i1nv i and which admit aintothe C,ylinle1'froin,., proved eon'ipressorunloader, andihasfor andthe-air.space 151 Surrounding ,the Same i object -to provide'a device .o'tthisV char- `oneside, air being admittedto thiSlSpeC. aeter adapted to beauton'iatieall-y actuated.through a Ppolfm The@Cylllldel-y 4S Sites through the pressure in. the receiver to prif'ldedetG3911 @Htl Wllh :OUlGWlYUSAlT' maintain a predetermined operati-ug'. pres-y UOF releasing.jtheeCOlllPllCSSGCl ilu IOlHfhGlI; sure, irrespective ol-theV variatien. in mthe.M CyliIlClel',i0 ,the SPMQS ,21ml IOIXLVhCh, consumptioneof `the-eornpressedh'anediunnNTIS ,CarriedithrouglrrthinteiQQOlQl C011- and which willfbe positive and reliable in .Cllllt 19 t0 tlletinltfSPiLC QIOfhLllghwn operation. i pressure.ylllldl ,.A

Otheriobjeets are to prov-idea devieeuorf y The, high .pressure Cylinderwis providedm. 2e this character, which may be readily assen'i--y ateaeh endk witlraminlet. valve, ilrdieated `g bledl and installedasfa 4complete:unitgiii 21S l-lliwnglllllQadermeanssaeeordinglto the coinpressoigaml which will lie-.free Offthlfplllti1ivl1f,0l1, :fOl ldmttlig $11,@ 75 any partsthat/will readily gement @tpl-der. '.ompressed air frenlftliespace 20, totliecyl-a- With the abo-ve. and Other-.Objectslin View, luder., amlfalseplzovlded ateecllvend4 with embodiments of the Ainvention are shown in ..0{ltllLV1YQS-17Q11 I llill @he CQMPFQSSQ@ at the accompanyingdrawings..a11cl.tliese ein?. 311% flQllllhG C VlHlClelf; t0 hanill SPQQQL y hodiinentsf will' be hereinafter.inore fully: and Afrom :Whlhffit `lS CODClBCQQl IlOy ,k1 PPS lso described with reference. theretonnd the.,22t0 il, 1GCGV61`.,.1}0l3;,Sh0WIL invention will lne-finally;pointedhouthinathe s In hQs-lelltvJHUSWLQQthGvPStOlS of.,

elainns. 'the LL reslzqeetiife cylinders* arey :attaehed to ini-y In the drawings; dependent running geargjbutit will zloemuneinloodinient of the invention; "GDODNS@11901215013 Clin the inlet WVQS,

Fig. isa plan view. oftheliftersi'orming v SDCL iS :.ilCllD-,tl UPQHLP :ledftelnnd Pres?y 95 part et the unloader; Sure beingl pr( due e dv in theX reeeiverI to Lhe Fig. 5 is a plan Lview. of theeinlet .valve `operated to open said valves, thevalves he-I stop plate; ing automatieally *closedV when .tlre\ p1;essure Fig` 6 is a vertical see-tional viewfofte .is relieved'i Fonthispurpose airgis admit-4 inodiiied form ,of thedeviee..` tednndenpressureto,the nnleadersthrough y100 Referring to theA drawings, the Vair eema series of.pipelinesironrtlie receiver, conf presser illustrated inl Figszl and 2, andin sisting in. theexalnple showninzii'gsl and which the unloader devices -aecordingyto 2 of a pipeQSlrOinthereceiver connected the present invention are ineorporatech'iis y to two Control. valve-s. Q-/land 25, ,which may, of the cross compounded multi-'stage type, be set Jfor any predetermined.operating'presn 105 and comprises a low pressure eylinder lOl-sure at whielritgis desirableorthe rniloader to operate. The valve 24 is connected by a pipe 26 to the rear inlet valve of the high pressure cylinder and by a pipe 27 to the front inlet valve oit the low pressure cylin der, while the valve is connected b y a pipe 28 to the rear inlet valve of the low pressure cylinder and by a pipe 29 to the iront inlet valve ot the high pressure cylinder.

Each valve is provided with a complete unloading mechanism and the total number of inlet valves is connected in parallel with the air lines, so that each valve may receive the identical ope ating pressure at the same instant. lVith this arrangement, as applied to the double acting compressor shown, the unloaders of the inlet valves of the high pressure cylinder are operated by the same means applied to the inlet valves of the low pressure intake cylinder, and in the same proportion on complementary ends of the compressing strokes, so that if one end of the intake cylinder be unloaded the proper end of the second stage cylinder is unloaded in like amount. In this way the mechanical balance of the compressor is maintained and improved operating conditions gained by producing smoother operation.

The unloader, according to the present invention is shown in Figs. 3 to G, Fig. G showing a slightly modiiied to'm of con struction than that shown in Figs. 3 to 5.

The cylinder wall is provided with an air chamber 30 having a valve controlled port 3l provided with an annular Valve seat shoulder 32, and in radial alignment with said port the outer wall of the chamber is provided with a circular opening 83 having an annular closure or bonnet seating shoulder 33a. The inlet valve and unloader is adapted to be engaged and seated as a unit in said port 3l and opening 33, The valve is of a type adapted to close during the compress-ion stroke of the piston and open during the admission stroke, and comprises a cage consisting of a valve guard or stop member 34 having an annular flange 85 seated on the shoulder 32, and a valve seat member 36 provided with an annular iiange 37, said seat having marginal closure contact with the stop member, a valve space 88 being provided between said stop and seat. The stop and seat are assembled-to form a valve unit by means of an internal threaded stud 39.

The stop member, shown in plan in Fig. 5, is provided with a plurality of annular inlet openings 40 having radial portions 4l forming connecting webs, and in the solid portions between said openings there are provided, at suitably spaced points, a plurality of spring seats or pockets 42, in which are placed the valve springs 43 which press upwardly upon the valve ringmembers 44 having spaces between them in register with the openings 40 and being normally pressed against the valve seat.

The valve seat 36 is provided with a plurality of spaced and radially disposed inlet passages 46 out of register with the openings 40 of the valve stop and normally closed by the solid ring valve members 44 in the normally engaged position of the members with the seat. In operation the valve members are seated during the compression stroke oit the compressor piston to close the passages 4G, while during the admission stroke the same is drawn against the stop, opening the inlet passages 46 and providing intake communication with the cylinder through the registered valve ports and the openings 4() of the stop.

rlhe valve bonnet 47 which is engaged in the seat 34 against a sealing gasket 48 is secured by suitable bolts 49, and 'is provided with a central threaded opening 50 in which a locking stud or bushing 5l having wrench engaging notches 52 is secured.

A valve retaining yoke comprising a relatively large ring 53 engaging the tlange 37 of the valve seat member 36, a smaller ring 54 disposed beneath and engaged by the lower end of the stud 5l, and radial connecting arms 55 between said rings, is pressed downwardly by the/ stud and clamps the valve in place.

The upper end of the stud extends above the bonnet and has screwed therein the overhanging internally threaded nut portion 56 of a cylinder member 57 disposed within and extending downwardly in the stud. The chamber 58 of the cylinder member has a reduced inlet passage 59 provided at its upper end with a threaded portion G() for connection of the pressure pipe line 'from the receiver. Vithin the chamber there is provided a plunger Gl having suitable packing rings 62, and at the lower end of the plunger within the space enclosed by the valveretaining yoke there is provided a `spider shaped valve lifter, comprising a central hub portion 63 and radial arms 64 having depending lingers 65 extending into the inlet passages 46 of the valve, a spring G6 engaged in a socket 67 of the hub GS and bearing upon the valve seat member normally retaining the lifterl in its raised or inoperative position, with the stop portions 68 of the arms abutting the ring 54 of the valve retaining yoke. An annular ring 69 is integrally formed between the arms G4 'for strengthening, and also for cooperation with manually operable means, presently to be more fully referred to, for manually opening the valve.

The operation of the device is as follows:

Vhen the pressure in the receiver reaches the predetermined point at which the control valves 24 and 25 operate, air under pressure is admitted to the chamber 5S and Sit) lll() fl T the plunger is advanced vto depress the valve litter, which moves downwardly through te it against the stop member, where it 1s held until the pressure in the `ri-iceiver has been valves 241 and 25 close, the 'spring (3.6 there upon raising the valve litter'and plunger Upon occasion itis desirable to open `the valve .inanually, as when starting "the coinprf erably tour, equally spaced plungers T() are mounted in vertical passages 7l ot in the ring GS) et the litter, being limited iu their upward movement by beveled shoulunder side ot'the bonnet. The upper ends of the plungers proyect above the bonnet ably mounted upon a. reduced portion of the cylinder inen'iber and retained thereon tion, the, lever being provided at suitably spaced points with beveled cumming por,-

to depress the plungers, which in turn depress the litter, thereby opening the. valve.

tions through it'urther turning ot the handle the litter is permitted to raise under kthe closed.

in Fig. 6 there. is illustrated a. modiiied of smaller diameter than that of the other form, and the arms oi the litter 78 are cortorni, being provided with two depending valve. opening lingers rather than three. ln

means, the nut portion 79 of the plunger cylinder member being flat on top, as disthe other torni. lt will be understood, of course, that manual operating means could the passages #i6 and opens the valve, movin 0' reduced to a point at which the control and permitting the valve to close.

pri sor, and 'lor 'this purpose a plurality,

the bonnet and are engaged in pockets TO ders 72 engaging beveled seats 7f3 in the and are engaged by a hand lever 74 rotatby a nut TG screwed upon said rediiced portions il' adapted upon turning oi' the handle Upon disengagen'ient ot the camming porpressure oit the spring 6G and the valve torni ofthe invention in which the valve is respondingly shorter than those of the other this torni, also, there is no manual operating tingnished 'from the reduced end portion in be incorporate-d in this form in the same manner as disclosed in Fig. 8.

l have illustrated and described preferred and satisfactory embodiments of the invention, but it will be understood that changes may be made therein, within the spirit and scope thereot, as defined in the appended claims.

Having thus described my invention, what l claim and desire to secure by Letters Patent is:

l. ln combination with an inlet valve oi a compressor, a pressure actuated unloader comprising a valve litter, a plunger tor depressing said litter, a pressure 'ylinder in which said plunger operates, a support surrounding said cylinder, valve retaining means interposed between said support and the valve for securing die vai ve 'ufponfits seat, and' meansadjustable through the sup'- pcrtfor mounting the cylinderandi-engaging the valve retaining means tofhold it against casualmovement.` f

2.Y lin combination with an inlet valve ot a compressor, a pressure actuated yunloader coin'ln'ising avalve litter, a plungeri'inedly secured 'to said litter ior depressing *the saine, a member including a pressure cylinder inv which `said plunger operates, asupport 'surrounding said-member and cylinder, said member having a portion extending at the opposite side et the support trom that at which the valve is located, manually operable means ior dianessing` the valve litter and including a lever mounted on the extension of said member, and valve retaining means interposed between said support and the valve for securing the valve upon its seat.4

In combination with an inlet valveoil a compressor, a pressure actuated unloader comprising` a valve litter, a plunger for depressing said litter, a member including a pressure cylinder .in which said plunger opH crates, an annular valve retainer surrounding said litter and engaging said valve at its marginal portion to secure it upon its seat, and means adapted to press said retainer in engagement with said valve, said means surrounding and supporting said member and being rotatable into and out oi engagement with the retainer.

Ll. ln combination with an inlet valve of a compressor, a pressure actuated unloader comprising a valve lifter, a plunger for depressing said '.lii'ter, a pressure cylinder in, which said plunger operates, a valve retainer engaging said valve to secure it upon its seat, a support annularly surrounding said cylinder, a cylindrical. externally threaded member engaged in said support, said pressure cylinder being supported and extending downwardly in said member, said member being engaged at .its lower end with said valve retainer to press the same in engagement with said valve.

5. ln combination with an inlet valve of a compressor, a pressure actuated unloader comprising a valve lifter, a plungeror depressing said lifter, a pressure cylinder in which said plunger operates, an annular valve retainer surrounding said lifter and engaging said valve at its marginal portion to secure it upon its seat, a support tor said cylinder, and means on said support engaging said valve retainer in annularly and outwardly spaced relation to said cylinder and adapted to press said retainer in engagement with said valve.

G. In combination with an inlet valve of a compressor, a pressure actuated unloader comprising a valve lifter, a plunger for de pressing said lifter, a pressure cylinder in which said plunger operates, and manual means directly engaged with said lifter for manually depressing it independently of the plunger. p

7. In combination with an inlet valve of a compressor, a pressure actuated unloader con'lprising a Valve lifter, a plunger :for depressing said lifter, a pressure cylinder in which said plunger' Operates, a support for said cylinder annularly surrounding the saine7 plungers operating` through said support directly engaging said lifter, and inunual means for operating said plungers to manually operate the lifter.

8. In combination with an inlet valve of a compressor, an unloader comprising a valve lifter, means for depressing said lifter, said means including plungers directly engaging said lifter at equally spaced points about its center, and means for manually depressing the plungers.

Signed at lnidgeport this 11th day ol Aug., 1924.

, ALBERT F. PARKS. 

